Currently the GPIO Aggregator does not support interrupts. This means that kernel drivers going from a GPIO to an IRQ using gpiod_to_irq(), and userspace applications using line events do not work.

Add interrupt support by providing a gpio_chip.to_irq() callback, which just calls into the parent GPIO controller.

Note that this does not implement full interrupt controller (irq_chip) support, so using e.g. gpio-keys with "interrupts" instead of "gpios" still does not work.

Signed-off-by: Geert Uytterhoeven geert+renesas@glider.be --- I would prefer to avoid implementing irq_chip support, until there is a real use case for this.

This has been tested with gpio-keys and gpiomon on the Koelsch development board:

- gpio-keys, using a DT overlay[1]:

$ overlay add r8a7791-koelsch-keyboard-controlled-led $ echo gpio-aggregator > /sys/devices/platform/frobnicator/driver_override $ echo frobnicator > /sys/bus/platform/drivers/gpio-aggregator/bind

$ gpioinfo frobnicator gpiochip12 - 3 lines: line 0: "light" "light" output active-high [used] line 1: "on" "On" input active-low [used] line 2: "off" "Off" input active-low [used]

$ echo 255 > /sys/class/leds/light/brightness $ echo 0 > /sys/class/leds/light/brightness

$ evtest /dev/input/event0

- gpiomon, using the GPIO sysfs API:

$ echo keyboard > /sys/bus/platform/drivers/gpio-keys/unbind $ echo e6055800.gpio 2,6 > /sys/bus/platform/drivers/gpio-aggregator/new_device $ gpiomon gpiochip12 0 1

[1] "ARM: dts: koelsch: Add overlay for keyboard-controlled LED" https://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers.git/co... --- drivers/gpio/gpio-aggregator.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/gpio/gpio-aggregator.c b/drivers/gpio/gpio-aggregator.c index 34e35b64dcdc0581..2ff867d2a3630d3b 100644 --- a/drivers/gpio/gpio-aggregator.c +++ b/drivers/gpio/gpio-aggregator.c @@ -374,6 +374,13 @@ static int gpio_fwd_set_config(struct gpio_chip *chip, unsigned int offset, return gpiod_set_config(fwd->descs[offset], config); }

+static int gpio_fwd_to_irq(struct gpio_chip *chip, unsigned int offset) +{ + struct gpiochip_fwd *fwd = gpiochip_get_data(chip); + + return gpiod_to_irq(fwd->descs[offset]); +} + /** * gpiochip_fwd_create() - Create a new GPIO forwarder * @dev: Parent device pointer @@ -414,7 +421,8 @@ static struct gpiochip_fwd *gpiochip_fwd_create(struct device *dev, for (i = 0; i < ngpios; i++) { struct gpio_chip *parent = gpiod_to_chip(descs[i]);

- dev_dbg(dev, "%u => gpio-%d\n", i, desc_to_gpio(descs[i])); + dev_dbg(dev, "%u => gpio %d irq %d\n", i, + desc_to_gpio(descs[i]), gpiod_to_irq(descs[i]));

if (gpiod_cansleep(descs[i])) chip->can_sleep = true; @@ -432,6 +440,7 @@ static struct gpiochip_fwd *gpiochip_fwd_create(struct device *dev, chip->get_multiple = gpio_fwd_get_multiple_locked; chip->set = gpio_fwd_set; chip->set_multiple = gpio_fwd_set_multiple_locked; + chip->to_irq = gpio_fwd_to_irq; chip->base = -1; chip->ngpio = ngpios; fwd->descs = descs;